Agriculture Reference
In-Depth Information
Ideal Soil Nutrients
60-75% calcium (60% for grasses and sandy soils)
7-15% magnesium (10-20% for grasses and sandy soils)
2-5% potassium
0.5-3% sodium
10-15% hydrogen
One reason you want to find a good lab and stick with it is because they will have their
own precise set of ideal numbers based on the procedures they use. Neal Kinsey works
with Albrecht's exact system, and he wants the numbers to be very close to 68% calcium
and 12% magnesium. He says he won't give you recommendations based on another lab's
test because he doesn't know the intricacies of their procedures. They may have found that
75% is the ideal calcium percentage based on their methods, and that's just fine. He finds if
you get below 10% or above 12% magnesium on his test, you'll probably run into some is-
sues.
It may seem somewhat arbitrary to focus on only these few nutrients. While it's true that
there are many other nutrients needed mostly in smaller amounts, Albrecht arrived at the
conclusion that these main ones are the most important to get right, especially in the begin-
ning of a soil management program. Overall, Albrecht's work has been ignored by conven-
tional agriculture, but championed by ecological farmers and gardeners. You won't learn
about it in most gardening and farming courses, but buy some topics from Acres U.S.A. or
go to their annual conference and you will learn more about these topics.
One other criticism of this test is that in order to extract the minerals from the soil
sample, labs use some fairly strong acids. They argue that these acids release nutrients that
aren't really available to plants because they are so tightly held by the soil that plants can't
extract them. This is partially true for many labs, but Albrecht didn't use the very strong
acids that many labs use. They were certainly stronger than the acids used in the Reams test
I'm going to show you next, but Albrecht was very concerned with finding the plant-avail-
able nutrients, too.
The analogy often given is that strong acids tell you what you have in your long-term
soil savings account. Weaker acids tell you what's in your soil checking account, so which
nutrients are more readily available to your plants. Using water instead of acids tells you
what you have in your pocket, so which nutrients are available today, but not necessarily
tomorrow. The strong acids pull too many nutrients and the water-soluble tests don't pull
enough. The weak acids are the most useful, and while I agree this Albrecht test is not per-
fect, I've seen how it's useful to compare year after year results and look at the trends.
